#include <omp.h> 
#include <stdio.h>
#include <math.h>
#include <stdlib.h>
static long num_steps = 2E9; 
double step; 
#define MAX_THREADS 50
int threads[] = {1, 2, 4, 6, 8, 10, 20, 30, 40};
int threads_list_num = 9;